High voltage power supplies are needed for many types of electronic devices. A low voltage may be converted to the appropriate high voltage by a transformer and associated signal conditioning components to obtain the desired voltage and current level. Often multiple electronic components and systems are powered by a single power supply. However, some types of loads may need individual current control. Typical power supplies provide global voltage or current control, but not individual voltage or current control for each of a number of outputs. A common solution is to provide a separate regulated power supply for each load or a subset of loads but not the entire set of loads, increasing the size and cost by including a transformer and filtering and control circuitry for each load or subset of loads.
An exemplary prior art power supply is illustrated in FIG. 1, in which a transformer 2 and full bridge rectifier 4 are used to convert an alternating current (AC) input 6 to a full-wave rectified current to power a load 8. The full bridge rectifier 4 comprises four diodes, with two input nodes at anode-cathode junctions between diodes. The full bridge rectifier 4 also comprises two output nodes, one at a cathode-cathode junction between diodes to which the load 8 is connected, and one at an anode-anode junction that is typically grounded. As is known, a direct current (DC) signal may also be provided to the load 8 by connecting a capacitor (not shown) between the output at the cathode-cathode junction of the full-bridge rectifier 4 and ground, thereby smoothing the full-wave rectified current to DC.